Rotary impact tools are used to tighten or loosen fasteners. Rotary impact tools often include a drive motor with a motor shaft, a hammer driven by the motor shaft, and an anvil that is impacted by the hammer so that the anvil is rotated and thereby drives a fastener. Most impact mechanisms are configured to transmit high-torque rotational force to the anvil (and subsequently a fastener) while requiring relatively low-torque reaction forces be absorbed by the motor and/or an operator holding the rotary impact tool. More specifically, by using the motor to repeatedly accelerate the hammer while it is out of contact with the anvil and then bringing the hammer only briefly into contact with the anvil, the anvil is imparted with a high-torque rotational force from the hammer impacts while the motor is exposed to low-torque reaction forces corresponding generally to the free acceleration of the hammer.